A bright star may be occulted by the asteroid 1 Ceres on early on Sunday, September 11th. If it happens, the event will be visible west of the Mississippi River between 11:34 and 11:35 Universal Time. Note that Ceres could conceivably have a satellite, so a 15-minute observing window is recommended. The 6.7-magnitude star is located almost halfway between 84 Geminorum and 4 Cancrii, about 20" southwest of NGC 2480-81; its 2000.0 coordinates are 7h 57m 6s, +23d 37.4'. Ceres will be magnitude 8.9. For more details, called the IOTA Occultation Hoitline at 301-474-4945.
It seems Periodic Comet Machholz 2 (1994o) is falling apart. As mentioned last week, a faint companion, about magnitude 11, was discovered 48 arc minutes from the primary comet in late August. But then a third piece was discovered late last week, and now two more fragments have been found. All but the primary are very faint; part B is near 13th magnitude now, and C, D, and E are 14th or 15th. However, Part A remains fairly easy to spot in the predawn sky. Observer Bill Smith of Ukiah, California, says the primary has a distinct, blue-green coma perhaps 15 arc minutes across and a pencil-thin tail extending more than 1 degree to the west. It's at least 7th magnitude and maybe closer to 6th. Here are positions for 0 hours Universal Time and equinox 2000 coordinates:
R.A. Dec. ============= Sept. 11 8h 23m +32.2 deg Sept. 13 8 30 +30.4 Sept. 15 8 37 +28.7
By the way, the latest calculations suggest that P/Machholz 2 has a 5.4-year orbit that ranges from just outside that of Venus to just beyond Jupiter.
Somewhat overlooked in the recent buzz over Machholz 2 is Comet Nakamura-Nishimura-Machholz, 1994m. The latest brightness estimates place it near magnitude 9 and fading. Also, it has begun to dive into the southern latitudes that will soon render it unobservable from the United States. Here are coordinates for the coming week:
R.A. Dec. ============= Sept. 11 21h 33m -15.5 deg Sept. 13 21 27 -19.8 Sept. 15 21 21 -23.5
The dark spots left behind on Jupiter by Comet Shoemaker-Levy 9 continue to evolve, say observers. Carlos Hernandez reports that there seems to be intense activity within around the spot left by fragments K and W. Even though Jupiter is sinking lower in the evening twilight each night, this is a particularly good time to be making observations, because many professional observatories have ended their Jupiter-watch programs. According to British observer John Rogers, the System II longitude of the K/W complex is roughly 160-205 degrees, the L spot is 225-260, and the D/G/S combo is 285-328.